Check list for view camera users

by Howard Bond, copyright © 1997.
1095 Harold circle, Ann Arbor, Michigan 48103
Reproduced with permission for the Large Format Page

This article was published in Photo Techniques, May/June 1998, pages 41-45 as "Setting up the View Camera". Scanning from the author's manuscript.

Some of my workshops involve view camera use, and participants bring to them many different brands of cameras. A few are monorails, but most are the more easily carried flat bed type. Because of the variety of cameras I help people with, I need to provide explanations and procedures that work with all view cameras.

This checklist grew out of more than 30 years of view camera use and before that, another 15 years of less flexible large format use. During the last 20 years, I have been teaching view camera techniques. Among the Photo Techniques readers who use view cameras, special circumstances or equipment may make it appropriate for some to take shortcuts, but most will profit from attention to all ten items on the list.

1. USE A COMPOSING CARD to plan exactly what will be included in a photograph, the camera position, and which lens to use. This is a card with a hole having the same proportions as prints. A 7"x9" piece of mount board or gray card with a hole no smaller than 3"x3-3/4" is convenient for the 4x5 proportion. Seen through this card, subjects look like finished, mounted prints, and you will be able to compose better and faster than by looking through the camera. One day recently, I forgot my composing card and was impressed by how much more difficult and inconvenient it was to operate a view camera without it. Instead of simply changing the distance from the card to my eye to try including various amounts of the subject, I had to take time to change lenses for these experiments.

When you get accustomed to your composing card, the distance from your eye to the card will tell you which lens is needed. And sometimes, the card will tell you there is no picture there and you won't have to set up the camera at all! More often, though, I see compositions through the card I never would have seen without it. It is surprisingly easy to find strong designs in the most unpromising subjects when looking through the card.

2. LEVEL THE CAMERA. If the horizon isn't visible and there are no parallel lines in the subject, this admonition need not be followed strictly.

3. FOCUS VERY ROUGHLY with the focus knob, rather than swings or tilts, just enough to see what is included on the groundglass.

4. USE SHIFTS TO POINT THE CAMERA at what you selected with the composing card. If the subject has parallel vertical lines you want to preserve, keep the back vertical and aim the camera up or down with front and/or rear vertical shifts. If you want to keep the horizontal lines of a building parallel, but from your camera position it would be necessary to rotate the camera sideways to frame the picture, keep the back parallel to the building and use lateral shifts.

If your camera lacks some shifts, or they don't go far enough, you can use front and back tilts or swings to substitute for, or augment shifts. (Time out to agree on definitions. A tilt tips the front or back of the camera forward or backward, pivoting about a horizontal axis. A swing pivots about a vertical axis.) If you need mere rising front than you have, point the whole camera up and tilt the front and back forward so that the groundglass and lensboard are again vertical. If you need more lateral shift, point the whole camera in that direction and use swings to return the groundglass and Iensboard to being parallel to the subject.

5. CHOOSE THE BEST LOCATION FOR THE PLANE OF FOCUS. To begin defining "best location", a digression is necessary. A principal reason for using 4x5 and larger cameras is that less enlarging is required to reach a given print size, and this can reasonably be expected to result in sharper prints. If a large camera lacks view camera movements, as most Graphic and Graflex cameras do, the only way to get enough depth of field is by the use of small apertures. With the long focal length lenses typical of large cameras, these apertures can be extremely small. But it is an unavoidable law of physics that diffraction causes a lens to resolve less and less as it is stopped down beyond its sharpest aperture, which may be near f8 for a good f5.6 enlarging or normal view camera lens. This can often negate the benefit of larger film size in a camera that lacks view camera movements. The amount of resolution loss to diffraction that can be tolerated depends on the degree of enlargement, which is related to negative size. Therefore, I try to avoid apertures smaller than f32 for 4x5, f45 for 5x7, and f64 for 8x10 negatives. Contact prints from negatives made at f90 look sharp to me.

The swings and tilts of a view camera allow the user to place the plane of focus anywhere, rather than keeping it parallel to the film. With many subjects, this makes it possible to orient the plane so that apertures need not be so small in order for the depth of field to encompass the whole subject. It is the photographer's task to visualize where this plane can be placed so that parts of the subject project away from it as little as possible. In doing so, one must take into account that the zone of depth of field is about twice as deep beyond the plane of focus as on the near side of it, and is very shallow where the plane is near the camera. Students sometimes start fiddling with the camera movements before carefully deciding where the plane of focus should be. Many minutes later, they may be as far out of focus as when they began, or be focused on a plane that will require an unnecessarily small aperture. Without a disciplined approach, the urge to start manipulating the camera can be irresistible at a time when full attenUon should be devoted to deciding what plane to focus on.

6. MAKE AN INFORMED ESTIMATE OF THE AMOUNT OF SWING OR TILT NEEDED. The Focus/Check procedure (8.) will converge to the correct setting, even if you start from neutral or a bad guess, but fewer iterations will be needed and time will be saved if your initial estimate is close to the setting that will place the plane of focus where you want it. If the plane is to be tipped forward or backward from vertical, a tilt is needed. A swing will rotate it sideways.

Imagine the plane extended until it passes by the camera. If it is far from parallel to the groundglass, it will pass relatively close to the camera and a considerable swing or tilt is needed. If the plane is nearly parallel to the groundglass, it will pass far from the camera, and a small adjustment is required. When a tilt is used, it is common for the plane to pass the camera many feet underground and the appropriate adjustment is very slight. Novices often start with too much.

The initial estimate for a swing or tilt is likely to be close to correct if you visualize the plane of the lensboard and the plane of the groundglass out of parallel and extended until they intersect. The goal is to have them intersect in the plane you want sharp. If you succeed, you will have satisfied the Scheimpflug principle and the swing or tilt will be correct. Usually, though, some further refining is needed. Section 8. will provide an efficient way to do that.

Should a swing or tilt be applied at the front or back of the camera? Several factors influence this choice. If the plane of focus passes very near the camera, some of each may be required in order to get the front and back sufficiently out of parallel so that their planes converge in the nearby plane of focus. If the lens barely covers the film, back adjustments may have to be used, in order for the image circle of the lens to cover the film. A need to preserve parallel vertical lines in the subject argues in favor of using the front. Often, especially in nature, either front or back movements can be used. If a tilt is needed and you wish to make a foreground object appear larger, use the rear tilt so the light rays from this object will have farther to travel from the lens to the film. It is important to know that this change in the relative size of near and far objects occurs whenever rear movements are used, but front swings and tilts don't alter sizes or shapes.

7. CHOOSE TWO FOCUSING TARGETS. These should be in the plane that is to be made sharp and at different distances from the camera so their images will lie some distance apart on the groundglass, one above the other for a tilt, and beside one another for a swing. Sometimes two suitable targets aren't available in the plane to be made sharp. In that case, you can take advantage of the fact that a tilted plane of focus moves parallel to itself when the focus knob is turned, just as it does with a rigid camera. Choose two targets that are in a plane that is parallel to the one you want to make sharp. After these target images have been made sharp with the help of a swing or tilt, turn the focus knob to move the focus to the desired plane.

8. USE THE FOCUS/CHECK PROCEDURE TO PERFECT THE TILT OR SWING. A nice feature of this procedure is that, in addition to quickly refining the adjustment from an initial estimate to the correct position, it tells you at each step along the way whether you should increase or decrease the magnitude of the movement. In Focus/Check, the word focus has its usual meaning - turn the knob back and forth while watching with a loupe, and stop when the image is sharpest. The word check means turn the knob in one direction only (i.e., give it a "tweak") while watching the image with a loupe.

Imagine you are looking at the camera from behind. We could refer to the upper and lower points on the groundglass where the focusing targets for a tilt would be imaged. You can use either of these points to focus on and the other to check. I tend to focus on the one that is harder to see and check the one that has finer detail or better contrast. Similarly, we could refer to the left and right points on the groundglass where focusing targets for a swing would be imaged. Again, either of them can be chosen for focusing and the other for checking. In all cases, the distance from the point used for checking to the corresponding edge of the lensboard is defined as d.

As an example (See Figure 1) suppose the back of the camera is tilted away from the lens according to an informed estimate (6.) and two focusing targets in the plane to be made sharp have been chosen (7.). Furthermore, the lower target image point on the groundglass has been selected for focusing (call it Pf), and the upper one for checking (call it Pc). Then d is the distance from Pc to the top edge of the Iensboard.

Focus on Pf, and for the first check at Pc, tweak in whichever direction you wish. Suppose your first check decreases d by moving the top of the lensboard and the top of the groundglass closer together. If the image at Pc gets sharper, you should incorporate the decrease of d into the tilt by removing some of the tilt. Focus/Check again, tweaking in the same direction because the last direction was beneficial. Suppose the image gets a little sharper and then gets fuzzier during the last part of the tweak. That indicates the direction was helpful and you are nearly correct. Decrease d slightly by removing a very small amount of tilt. Focus/Check again, tweaking in the same direction. Suppose the image immediately gets fuzzier. This would happen if the tilt is exactly right or if you removed too much tilt the last time you adjusted it. To find out which is the case, don't change d (because the tilt might be correct) but do a Focus/Check, tweaking in the opposite direction. If the image gets fuzzier, the tilt is correct and you are finished. If it gets sharper before getting fuzzier, your last tilt adjustment removed too much and you need to increase d by slightly increasing the tilt. You will learn to judge the magnitude of changes needed by noting how image sharpness changes as you tweak the focus knob.

It will soon become apparent that changes of tilt or swing must be very slight as you near convergence. With many view cameras, these adjustments can be made much more accurately if you will come out from under the dark cloth and look at the camera piece you are moving. This also makes it easier to see whether d increases or decreases during a check and to decide whether more or less swing or tilt is needed. Resist the temptation to try to do everything by feel while looking at the groundglass. After manipulating various view cameras for decades, if a movement isn't easy to control, I still come out from under the dark cloth and watch while adjusting it.

After tweaking the focus knob for a check, many students seem to have an uncontrollable urge to turn the knob again in the opposite direction (while still looking at Pc). Since Pf is now out of focus, nothing more can be learned, so use the information provided by the initial tweak to modify d, and start a new Focus/Check. There is never any reason to turn the knob in two directions while watching Pc.

If the horizontal axis about which the back of the camera pivots during a tilt coincides with the center of the groundglass (or somewhat lower, as with certain monorail cameras) and if one can manage to have the image of one of the focusing targets fall on this axis, marvellous efficiency is possible. The distant target is focused at the axis with the focus knob and it stays in focus while the near target (whose image is higher on the groundglass) is brought into focus simply by tilting the back. Some owners of cameras that pivot on an axis at the base of the back, below the ground glass, try to operate this way. They focus on the lower target image point and then tilt the back until the upper point is in focus. However, since the lower point isn't on the axis, it goes somewhat out of focus during the tilt. This procedure could be used as an initial estimate of the tilt needed, but the Scheimpflug principle might provide a closer one.

Focus/Check is useful for all types of view cameras, but two types of camera construction restrict the choice of which point on the groundglass to use for Pf and which for Pc. If the tilt being used pivots at the base, use the focusing target point closest to the base for Pf and the higher one for Pc. This allows needed changes in d to be applied directly to the tilt. Similarly, some wooden Japanese cameras accomplish swings by holding one side still and flexing a strut to move the other side. In this case, choose for Pf the point closest to the side that doesn't move.

Although Focus/Check is simple when applied to a specific example, many words are needed to describe it, as the above example demonstrated. Attempts to state the procedure in a general way that covers both swings and tilts simultaneously quickly become ponderous and confusing. Therefore, my general presentation is in the form of a flow chart that works for both movements. See Figure 2 . I recommend practicing with the camera and flow chart to become more familiar with Focus/Check.

9. CHOOSE THE LARGEST APERTURE THAT WILL PROVIDE ADEQUATE DEPTH OF FIELD. Typically, some parts of the subject project away from the plane of focus. After focusing, choose the fuzziest of these, ideally a bright one, and watch the image with a loupe while slowly stopping down until it looks sharp. If the negative will be enlarged a lot, stop down another stop, if you can do so without unacceptable diffraction loss. If it does seem that diffraction will be a problem, review the location of the plane of focus and see if a better orientation (one that requires less depth of field) could be chosen. Or, it might pay to explore minor variations in the composition or camera position that might have less severe depth of field requirements. When the aperture needed for depth of field would incur an undesirable diffraction loss, it is well to remember that insufficient depth of field is likely to be obvious, while the overall degradation caused by dffraction is usually subtle. Therefore, I give priority to depth of field.

10. RETURN THE CAMERA MOVEMENTS TO NEUTRAL. If you put away your camera with some swing on it, and its next use is for a photograph of your high school class at its 30th anniversary reunion, people in the middle of the front row will be in focus, while those at the ends will be soft. This will make you feel very bad! Please don't ask how I know that.

Throughout the presentation of this checklist, there was an unstated assumption that you would use either a swing or a tilt. Consider the possibility that you might need both movements for the same photograph. Suppose a subject is low where it is close to the camera and high farther away. Also, the subject is close to the camera on the right and farther away on the left. This calls for an oblique plane of focus, tipped away from the camera and also rotated. This can be achieved by using both a tilt and a swing, applied sequentially. It doesn't matter which is done first.

For an example that is easy to describe, assume that a tilt and a swing are to be done at the back of the camera, with the tilt to be applied first. Choose two focusing targets in the desired plane whose images will lie one above the other on the groundglass. Estimate the tilt and then perform the Focus/Check procedure as though the tilt were the only movement needed. Next, do the estimate and Focus/Check for the swing. You can ignore the fact that a tilt has already been done, except for one requirement. Because the top and bottom of the groundglass are now different distances from the lens, Pf and Pc for the swing must be the same distance from the top of the groundglass. This is easy to arrange if your groundglass has grid lines - just have Pf and Pc on or near one of the horizontal grid lines.

If the swing had been applied first, the right and left sides of the groundglass would be different distances from the lens when you got ready to do the tilt. This would require the Pf and Pc for the tilt to be the same distance from the left edge of the groundglass (i.e., on the same vertical grid line). Rear swing and tilt were used for this example because this allowed me to talk in terms of distance from the lens. Combining a swing and a tilt works equally well if one or both adjustments are made at the front. Just be sure the focusing points for the second movement lie on the same grid line. If your groundglass lacks grid lines, draw them on the side toward the lens with a pencil and T-square.

Apparently, the simultaneous use of a swing and a tilt, with the Scheimpflug principle guiding the choice of initial estimates, seems rather daunting to some people. After a view camera workshop, one participant wrote that he had just done a "double Scheimpflug without a safety net" !

In summary

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